Date of Award


Degree Type


Degree Name

Master of Science (MS)


Kinesiology and Health

First Advisor

Jianhua Jerry Wu, Ph.D.

Second Advisor

Mark D. Geil, Ph.D.

Third Advisor

Feng Yang, Ph.D.


Long-range correlation has been observed in the time series of the human neuromuscular system and indicative of a healthy system. However, this analysis has not been used for an scenario of asymmetrical loading during walking. This study aimed to understand the effect of unilateral ankle loading on long-range correlation of spatiotemporal gait parameters in healthy young adults during treadmill walking. We used four unilateral ankle loads (A0, A25, A50, and A75, representing the increase of the moment of inertia of the leg about the knee joint by 0%, 25%, 50% and 75%, respectively) and attached it on the non-dominant leg. We used a modified lower-extremity marker set to collect kinematic data. Subjects walked on a treadmill at their self-selected speed for five minutes under each load condition. For data analysis, we used the toe and heel markers to identify the gait events of heel strike and toe off. We divided each five minute trial into three 100-second segments to investigate potential time effect. We calculated the mean and standard deviation of step length and step time, and conducted a detrended fluctuation analysis (DFA) and calculated the scaling exponent for every 100 seconds. For statistical analysis, we conducted three-way (2 side x 3 time x 4 load) ANOVA with repeated measures on step length and time. Our results demonstrate that mean step time and step length showed three-way interaction, in which step length increased with the load for both sides whereas step time increased on the loaded side but decreased on the unloaded side. Asymmetry between two legs decreased in step length while asymmetry in step time remained over time and across load conditions. DFA results revealed long-range correlation in step length and step time; however, step length showed only a time effect whereas step time showed neither a time nor a load effect. Our results suggest that there might be different control mechanisms on regulating spatiotemporal variables and its long-range correlation while walking with unilateral ankle load.